This book constitutes the refereed proceedings of the 18th International Symposium on Computer and Information Sciences, ISCIS 2003, held in Antalya, Turkey in November 2003.The 135 revised papers presented together with 2 invited papers were carefully reviewed and selected from over 360 submissions. The papers are organized in topical sections on architectures and systems, theoretical computer science, databases and information retrieval, e-commerce, graphics and computer vision, intelligent systems and robotics, multimedia, networks and security, parallel and distributed computing, soft computing, and software engineering.